I've been trying unsuccessfully to book a place close to the Frankfurt train station before flying out the next morning. All of Rick's recommendations are booked for the middle of October. Any suggesstions? Airport is expensive but might be our last resort. Also, will airport hotel shuttles pick you up from the airport if you take the train in before staying overnight?
Try staying in Mainz. It's only about 20 minutes by S-Bahn to the airport.
As I keep suggesting for cases just like yours: Try the IBIS hotel Frankfurt Centrum on www.hrs.de, www.hotel.de or www.ibishotel.de. It's just about a 5 mins walk from the train station, all rooms come with AC and it's a less than 3 mins walk down to the riverfront with all of its great restaurants, bars (even a floating cocktail lounge). From there you can walk to the heart of the city center simply by following the embankment. It's an all green, park like walk. Or you stay in the Westhafen (western harbor) area where there are also restaurants, bars, outside seating etc.
try booking at hrs.de for frankfurt or hotels.de
You may want to consider training directly to the airport from the city you are in the day before. We went directly from Munich to the airport with zero transfers the morning of our flight. I think most trains stop at the airport, but you need to make sure. It was really easy and one less bag drag.
Thanks everyone for the responses. I ended up booking a place near the airport, just so I'd have convenience of taking a shuttle to the airport the next morning.